DE202009013216U1 - Actuator for pedestrian protection device - Google Patents

Abstract

Actuator 1 with a tubular housing (2), with a closure part (3) with a fastening part (4), an out of the closed end of the housing (2) opposite end of the housing (2) led out piston rod (8) with a fastener thereon (9), a concentric in the housing (2) arranged and along the central axis (14) displaceable piston group (10), with a force acting on the piston group in the extension force means, characterized in that after pushing out the piston group (10) from the housing (2) the closure member (3) is pulled out of the housing (2) by the length X along the central axis (14).

Description

Technical environment

The The invention relates to an actuator, in particular for the Use in a pedestrian protection device for a passenger car.

From the DE 10 2007 009 096 A1 An energy storage device for a pedestrian protection foot device is known. In this document, the lifting of the front hood is described in particular in the windshield by means of a corresponding kinematics by a force storage. In addition, a device is disclosed which allows a provision of the kinematics in the position before the triggering of the energy accumulator with a lock. The locking device itself is complex and exposed to the environment.

The in the DE 10 2007 096 A1 described combination of a gas spring with an actuator is core of the cited invention. The still known documents DE 103 23 118 A1 . DE 101 44 792 A1 and DE 10 2004 004 987 A1 were already in the DE 10 2007 009 096 A1 appreciated accordingly.

Disclosure of the invention

Technical problem

To a collision of a motor vehicle with a pedestrian If the front hood is to be raised in less than 100 ms, so that the bonnet still remains after the impact of the pedestrian can deform sufficiently strong. This ensures that the reduces the acceleration acting on the pedestrian becomes. The hood should not swing after pivoting; The actuator should therefore be designed so that the hood is slowed down defined after swinging. Continue to it may be possible to use the front hood, z. After a false trip, to return to its original position and re-lock to allow onward travel.

The locking device should be integrated in the actuator and protected against environmental influences. The combination of the normal opening of the front necessary gas spring with the actuator as in DE 10 2007 009 096 A1 Although described is possible, but should not be described here. It is therefore the object to provide a fast, resettable actuator with integrated energy absorption device and locking.

Technical solution

To solve the above object, an actuator according to the 1 proposed. Preferably, the extension force is generated by a pressure gas generating unit. In principle, however, an externally supplied gas or fluid could also be used. The actuator consists of vinous parts and can be produced inexpensively. For energy absorption, no additional parts are needed; by appropriate geometric design in particular take over the housing of the actuator together with the piston unit, the energy intake and locking.

Short description of drawings

1 : Sectional view of the actuator before activation of the pressurized gas generating unit Fornthaube closed.

2 : Sectional view of the actuator after activation of the pressurized gas generating unit and after the full lifting of the bonnet

3 : Sectional view of the actuator after activation of the pressurized gas generating unit and after the recovery of the front panel in closed and locked position

4 : Detail display off 3

5 Position of the pedestrian protection device before activation of the compressed gas generating unit

6 Position of the pedestrian protection device after activation of the pressurized gas generating unit and after complete lifting of the front hood

7 : Position of the pedestrian protection device after activation of the pressurized gas generating unit in the closed and locked position

The best way, the invention exploit

The in 1 illustrated actuator 1 consists essentially of a cylindrical housing 2 that on one side with a closure part 3 is sealed gas-tight. The closure part is with the beads 21 in the case 2 secured against axial displacement. The closure part 3 is on the case 2 dismounted side with a fixing part 4 Mistake. In the closure part 3 is a pressurized gas generating unit 5 gas-tight to the closure part 3 accommodated. The compressed gas generating unit 5 is with at least 2 strands 6 connected to an external controller. At the other end of the case 2 there is an annular guide element 7 . through the coaxial with the housing 2 the piston rod 8th to be led. Not in the case 2 located end of the piston rod 8th there is a second fastener 9 ,

Am in the case 2 located end of the piston rod is the cylindrical piston group 10 , The piston group consists of an advantageous two-part piston 11 , a seal 12 and a locking mechanism 13 ; in a simple embodiment 1 - 3 If the locking mechanism consists of a radially biased locking ring. The piston group 10 can along with the piston rod along the central axis 14 be moved. Through the seal 12 the interior of the housing becomes gastight in the chamber 15 and 16 separated.

The actuator 1 to 1 is the housing side through the fastening part 4 with the base plate 18 and through the attachment part 9 with the kinematics 17 connected ( 4 ). The kinematics 17 is by a shearpin 24 in the in 3 shown position held. The Sherpin 24 is in the example shown a cylindrical pin in the lever 25 and in the base plate 18 located hole 26 is mounted.

If, after detecting a pedestrian collision by an external control, an electrical trip signal over the strands 6 to the pressurized gas generating unit 5 created, then builds up in a few milliseconds in the chamber 15 a high gas pressure on ( 1 ). The force resulting from the gas pressure acts on the piston 11 and moves the piston group 10 with the piston rod 8th along the central axis 14 in the direction of the chamber 16 , Due to the high pressure in the chamber 15 becomes a big pushing force over the piston 11 on the piston rod 8th transfer; this will be the shear pin 24 destroyed (destroyed) 5 ) and the front hood 19 through the actuator 1 about the kinematics 17 accelerated.

So that the front hood 19 in the in 6 shown swinging position as little as possible, is a defined braking the front axle 19 required before reaching the end position. In the case 2 of the actuator are therefore beads 20 provided by the piston group 10 deformed during extension. Due to the axial position, or length of the beads 20 in the direction of the central axis 14 it can be determined in which position the bonnet should be delayed; by the number and depth of the beads is contrary to the movement of the piston group 10 acting force determined. The piston group 10 with the piston rod 8th moves axially relative to the housing 2 until the piston 11 on the guide element 7 is applied.

The beads 20 are matched to the fronthaben mass that the front hood 19 still has enough kinetic energy to the closure part 3 out of the case 2 along the central axis 14 pull it out. The closure part 3 deforms beads 21 and thereby brakes the bonnet 19 continue down. By the depth and number of beads 21 becomes analogous to the beads 20 set the force counteracting the movement. In the end position, the closure part is axially pulled out of the tube by the length X ( 2 . 6 ). The sealing effect of the seal 22 in the closure part 3 to the housing 2 is in the bead area 21 restricted, so that the gas from the chamber 15 can flow out defined.

After a few seconds, the pressure in the chamber 15 dismantled and the front hood 19 can be counteracted by the actuator 1 generate moving direction to be moved back. Is the front hood 19 with the kinematics 17 again in the starting position as in 6 shown, the radially biased locking ring expands 13 radially on and snaps into the housing 2 introduced recess 23 a (position as in 4 . 7 shown). A locking of the piston group 10 , or the piston rod 8th with the housing 2 is possible, although the distance of the connecting parts 4 and 9 measured along the central axis in the in 1 and the in 3 shown position is the same.

To the length X, to the the closure part 3 to the housing 2 to 2 respectively. 5 is moved, after resetting the kinematics 17 , the piston rod 8th deeper into the case 2 plunge. This will also immerse the piston group 11 deeper and the locking device 13 locked to the housing 2 , The piston group 10 and the piston rod 8th is thus against axial pushing out of the housing 2 secured. The front hood 19 thus can not raise; the vehicle is ready to drive again.

1

actuator

2

casing

3

closing part

4

attachment portion 4

5

compressed gas generating unit

6

strands

7

guide element

8th

piston rod

9

fastener

10

piston group

11

piston

12

poetry

13

locking ring

14

Central axis actuator 1

15

chamber

16

chamber

17

kinematics

18

baseplate

19

bonnet

20

Bead (n)

21

Bead (n)

22

poetry closing part

23

locking ring

24

Scherpin

25

lever Kinemaik

26

drilling in the lever and in the base plate

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 102007009096 A1 [0002, 0003, 0005]
• DE 102007096 A1 [0003]
• - DE 10323118 A1 [0003]
• - DE 10144792 A1 [0003]
• DE 102004004987 A1 [0003]

Claims (5)

actuator 1 with a tubular housing ( 2 ), with a closure part ( 3 ) with a fastening part ( 4 ), one from the closed end of the housing ( 2 ) opposite end of the housing ( 2 ) led out piston rod ( 8th ) with a fastener ( 9 ), one concentric in the housing ( 2 ) and along the central axis ( 14 ) displaceable piston group ( 10 ), with a force acting on the piston group in the extension direction force means, characterized in that after the pushing out of the piston group ( 10 ) out of the housing ( 2 ) the closure part ( 3 ) about the length X along the central axis ( 14 ) out of the housing ( 2 ) is pulled out. Actuator according to claim 1, characterized in that after the pushing out of the piston group ( 10 ) by means of a gas-powered unit ( 5 ), the piston rod ( 8th ) with the piston group ( 10 ) along the central axis ( 14 ) by the length X deeper into the housing 2 can be inserted and the piston group in the fully inserted position by means of a locking mechanism ( 23 ) is secured against being pushed out again. Actuator according to claim 1 and 2, characterized in that the beads ( 20 ) 21 ) in the housing ( 2 ) together with the closure part ( 3 ), or the piston group ( 10 ), to reduce the kinetic energy of the front hood ( 19 ) be used. Actuator according to claim 1 and 2, characterized in that through the beads ( 20 ) and ( 21 ) defined leaks between the piston ( 11 ) and the housing ( 2 ) and between the closure part ( 3 ) and the housing ( 2 ) arise. Use of an actuator according to one of claims 1 to 4 in a pedestrian protection device for lifting a front hood ( 19 ) in the windshield area, where in kinematics ( 17 ) a shear pin ( 24 ) is provided, which only after actuation of the compressed gas generating unit ( 5 ) and a kinematics movement ( 17 ) allows.